mtd: nand: write BBM to OOB even with flash-based BBT

index 2d010e4..5822e3a 100644
@@ -386,15 +386,23 @@ static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
  * @ofs: offset from device start
  *
  * This is the default implementation, which can be overridden by a hardware
- * specific driver.
+ * specific driver. We try operations in the following order, according to our
+ * bbt_options (NAND_BBT_NO_OOB_BBM and NAND_BBT_USE_FLASH):
+ *  (1) erase the affected block, to allow OOB marker to be written cleanly
+ *  (2) update in-memory BBT
+ *  (3) write bad block marker to OOB area of affected block
+ *  (4) update flash-based BBT
+ * Note that we retain the first error encountered in (3) or (4), finish the
+ * procedures, and dump the error in the end.
 */
 static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
 {
 	struct nand_chip *chip = mtd->priv;
 	uint8_t buf[2] = { 0, 0 };
-	int block, ret, i = 0;
+	int block, res, ret = 0, i = 0;
+	int write_oob = !(chip->bbt_options & NAND_BBT_NO_OOB_BBM);
 
-	if (!(chip->bbt_options & NAND_BBT_USE_FLASH)) {
+	if (write_oob) {
 		struct erase_info einfo;
 
 		/* Attempt erase before marking OOB */

@@ -407,23 +415,17 @@ static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
 
 	/* Get block number */
 	block = (int)(ofs >> chip->bbt_erase_shift);
+	/* Mark block bad in memory-based BBT */
 	if (chip->bbt)
 		chip->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);
 
-	/* Do we have a flash based bad block table? */
-	if (chip->bbt_options & NAND_BBT_USE_FLASH)
-		ret = nand_update_bbt(mtd, ofs);
-	else {
+	/* Write bad block marker to OOB */
+	if (write_oob) {
 		struct mtd_oob_ops ops;
 		loff_t wr_ofs = ofs;
 
 		nand_get_device(chip, mtd, FL_WRITING);
 
-		/*
-		 * Write to first/last page(s) if necessary. If we write to more
-		 * than one location, the first error encountered quits the
-		 * procedure.
-		 */
 		ops.datbuf = NULL;
 		ops.oobbuf = buf;
 		ops.ooboffs = chip->badblockpos;

@@ -435,18 +437,28 @@ static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
 		}
 		ops.mode = MTD_OPS_PLACE_OOB;
 
+		/* Write to first/last page(s) if necessary */
 		if (chip->bbt_options & NAND_BBT_SCANLASTPAGE)
 			wr_ofs += mtd->erasesize - mtd->writesize;
 		do {
-			ret = nand_do_write_oob(mtd, wr_ofs, &ops);
+			res = nand_do_write_oob(mtd, wr_ofs, &ops);
+			if (!ret)
+				ret = res;
 
 			i++;
 			wr_ofs += mtd->writesize;
-		} while (!ret && (chip->bbt_options & NAND_BBT_SCAN2NDPAGE) &&
-				i < 2);
+		} while ((chip->bbt_options & NAND_BBT_SCAN2NDPAGE) && i < 2);
 
 		nand_release_device(mtd);
 	}
+
+	/* Update flash-based bad block table */
+	if (chip->bbt_options & NAND_BBT_USE_FLASH) {
+		res = nand_update_bbt(mtd, ofs);
+		if (!ret)
+			ret = res;
+	}
+
 	if (!ret)
 		mtd->ecc_stats.badblocks++;
 

@@ -3222,6 +3234,10 @@ int nand_scan_tail(struct mtd_info *mtd)
 	int i;
 	struct nand_chip *chip = mtd->priv;
 
+	/* New bad blocks should be marked in OOB, flash-based BBT, or both */
+	BUG_ON((chip->bbt_options & NAND_BBT_NO_OOB_BBM) &&
+			!(chip->bbt_options & NAND_BBT_USE_FLASH));
+
 	if (!(chip->options & NAND_OWN_BUFFERS))
 		chip->buffers = kmalloc(sizeof(*chip->buffers), GFP_KERNEL);
 	if (!chip->buffers)

index c4eec22..650ef35 100644
@@ -112,6 +112,11 @@ struct nand_bbt_descr {
 #define NAND_BBT_USE_FLASH	0x00020000
 /* Do not store flash based bad block table in OOB area; store it in-band */
 #define NAND_BBT_NO_OOB		0x00040000
+/*
+ * Do not write new bad block markers to OOB; useful, e.g., when ECC covers
+ * entire spare area. Must be used with NAND_BBT_USE_FLASH.
+ */
+#define NAND_BBT_NO_OOB_BBM	0x00080000
 
 /*
  * Flag set by nand_create_default_bbt_descr(), marking that the nand_bbt_descr